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1. Cobalt recovery from spent lithium-ion batteries by leaching in H2SO4-N2 and H2SO4-O2 systems followed by electrochemical deposition

Author

Medić Dragana V., Tasić Žaklina Z., Nujkić Maja M., Dimitrijević Silvana B., Đorđievski Stefan S., Alagić Slađana Č., and Milić Snežana M.

Subjects
cathode material, acid leaching, lithium-cobalt oxide, recycling, metal coating, Chemical technology, TP1-1185
Abstract

This paper is focused on cobalt valorization from the cathode material of spent lithium-ion batteries (LIBs) by using leaching and electrochemical deposition methods. During the leaching experiments, the degrees of cathode material dissolution in H2SO4-N2 and H2SO4-O2 systems were compared. Maximal degrees of cobalt extraction were 40 % in the former and 47 % in the latter system under following experimental conditions: H2SO4 concentration of 2 mol dm-3, nitrogen/oxygen volumetric flow of 2 L min-1, solid phase concentration of 33 g L-1, and temperature of 85°C. The rate of cobalt extraction from the cathode material in both investigated systems was the most favorable in the first 15 min, after which there was a sudden decrease in the reaction rate. Cobalt from the leaching solution was deposited on a copper substrate by galvanostatic electrochemical deposition with a current efficiency of 84 %. The energy consumption was 5.8 kWh kg-1 of deposited Co. The cyclic voltammetry (CV) method was used to determine the potential of cobalt deposition, as well as side reactions taking place in the system. Scanning electron microscopy with energy dispersive spectrometry has shown that during the process of electrochemical deposition agglomeration of cobalt particles occurred (in the shape of cauliflower), while the metal was deposited in its elemental state, which was also confirmed by the results of X-ray diffraction analysis.

Published
2024
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3. Walnut shells as a potential biosorbent for Cu(II), Pb(II) and As(III)/(V) ions removal from river waters

Author

Nujkić Maja M., Tasić Žaklina Z., Medić Dragana V., Milić Snežana M., and Stanković Sonja S.

Subjects
biosorption, walnut shell, metal/oids, natural material, wastewater, Technology (General), T1-995
Abstract

In this study, the potential of the walnut shell as a biosorbent for biosorption of Cu(II), Pb(II), and As(III)/(V) ions from river water samples was investigated. The effects of various conditions of water samples such as the initial ion concentration, sample pH, and contact time at a constant temperature and biosorbent dosage, on biosorption of Cu(II), Pb(II), and As(III)/(V) were investigated. Walnut shells, as the material with a high potential for removal of investigated ions, have biosorption efficiency of up to 99.6%, under the applied experimental conditions. The best adsorption time was obtained at 4 h for Cu(II), Pb(II), and As(III)/(V) ions. The maximum removal of 97.6% (Cu(II)), 82.9% (Pb(II)), and 99.6% (As(III)/(V)) was obtained at pH=4.43, pH=8.55, and pH=7.84, respectively. Hence, the walnut shell shows potential of a cost-effective biosorbent that could be used for the treatment of contaminated rivers. However, further investigation is needed to fully explore this potential.

Published
2023
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5. Application of microbial fuel cell for simultaneous treatment of metallurgical and municipal wastewater - а laboratory study

Author

Đorđievski Stefan, Yemendzhiev Hyusein, Koleva Ralitza, Nenov Valentin, Medić Dragana, Trifunović Vanja, and Maksimović Ana

Subjects
bor river, copper, organic matter, bacteria, electrochemical, prototype, Chemistry, QD1-999
Abstract

Microbial fuel cell (MFC) is a hybrid technology that produces electricity and recovers resources from wastewater through biocatalytic and electrochemical reactions. Metallurgical facilities in Bor, Serbia, are a source of copper-rich metallurgical wastewater, and the Town of Bor is a source of municipal wastewater rich in organic matter. The aim of this paper is to investigate the possibility of application of MFC for the treatment of metallurgical and municipal wastewater that are released into the Bor River in Serbia. A prototype of MFC was constructed for this study, and 3 sets of experiments were performed using model solutions and real wastewater. Copper was successfully removed from the treated model solution with 99.42 % efficiency. Solid copper particles were obtained with a particle size of about 1 μm. Maximum chemical oxygen demand (COD) removal rate of 191.7 mg L-1 h-1 was observed in the anodic compartment. The impact of this study is significant because MFC was implemented for the simultaneous treatment of two types of wastewaters, one containing metals and the other containing organic matter, and both types of wastewater are released into the same river.

Published
2022
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6. Prezentacija projekta Programa Prizma 2023 Fonda za nauku Republike Srbije: Proučavanje ciljnih mesta delovanja antihelmintika u neuromuskularnom sistemu parazitskih nematoda u cilju poboljšanja farmakoterapije i razvoja novih lekova

Author

Trailović, Saša M., Milovanović, Mirjana, Marjanović, Đorđe S., Medić, Dragana, Marinković, Darko, Aničić, Milan, Stojković, Maja, Trailović, Saša M., Milovanović, Mirjana, Marjanović, Đorđe S., Medić, Dragana, Marinković, Darko, Aničić, Milan, and Stojković, Maja

Abstract

Parazitske nematode su značajni patogeni životinja i ljudi. Nažalost, lekovi koji se koriste u farmakoterapiji helmintoza nisu apsolutno efikasni i bezbedni protiv svih kombinacija vrsta parazita/domaćina. Postoji jasna i hitna potreba za novim efikasnim antinematodnim jedinjenjima. Ova potreba postaje sve važnija sa sve većim nivoom rezistencije parazita na postojeće lekove. Većina anthelminika deluje na neuromišićni sistem nematoda. Mi u projektu predviđamo da se dalje ispita neuromišićni sistem na modelima parazitske nematode Ascaris suum i slobodnoživuće nematode Caenorhabditis elegans. Fokusiraćemo se na ispitivanje kombinaciju novih (muskarinski i serotoninski receptori) i prethodno potvrđenih potencijalnih ciljnih mesta (jonotropni nACh i GABA receptori). Predlažemo da se odredi lokalizacija ovih receptora u somatskim mišićima A. suum metodom RNA-scope in situ hibridizacije. Farmakološki ćemo okarakterisati ove receptore koristeći kombinaciju studija pokretljivosti, testova faringijalnog pumpanja (C. elegans), testova kontrakcije nervnomišićnog preparata (A. suum) i elektrofiziološkim metodama “voltage“ i „current clamp“ sa dve elektrode (A. suum). Koristeći ove tehnike, ispitivaćemo sledeće: 1. Efikasnost kombinacija postojećih GABA-ergičnih i holinergičkih lekova u cilju poboljšanja efikasnosti; 2. Potencijalno nove mete za anthelmintike (muskarinski ACh receptor i serotonergički MOD 1 receptor); 3) Prenamenu postojećih lekova koji ispoljavaju potencijalna anthelmintička svojstva; 4) Antinematodna svojstva terpenoidnih aktivnih sastojaka (AI) biljnih esencijalnih ulja i potencijal kombinacija AI i postojećih lekova. Očekujemo da će naši rezultati pružiti precizniju karakterizaciju postojećih (holinergičkih i GABA-ergičnih) i potencijalnih (muskarinskih i seretonergičkih) receptora za antiparazitske lekove. Utvrdićemo da li neki stariji lekovi imaju potencijal da se ponovo koriste kao anthelmintici, samostalno ili u kombinacijama.

Published
2024

7. Novine u veterinarskoj farmakoterapiji, propisivanje lekova na recept i stručno usavršavanje iz farmakologije i toksikologije

Author

Trailović, Saša, Milovanović, Mirjana, Ivanović, Saša, Marjanović, Đorđe, Medić, Dragana, Trailović, Saša, Milovanović, Mirjana, Ivanović, Saša, Marjanović, Đorđe, and Medić, Dragana

Abstract

Radionica na Katedri za farmakologiju i toksikologiju će se sastojati iz četiri dela: novine u veterinarskoj farmakoterapiji, prezentacije usavršavanja iz farmakologije i toksikologije, propisivanje lekova na recept i praktičnog dela primera propisivanja različitih veterinarskih i humanih lekova na veterinarski recept. U veterinarskoj farmakoterapiji već duže vreme nema novih lekova. Poslednji antibiotik koji je registrovan bio je tulatromicin još 2003. godine. Međutim, pritisak da se ograniči i smanji primena antimikrobnih lekova je sve veći. Komitet Evropskog parlamenta za životnu sredinu, javno zdravlje i hranu (ENVI) je 13. jula 2021. godine, podneo predlog rezolucije Evropskom parlamentu (EP), kojom se antimikrobni lekovi označeni od strane Svetske zdravstvene organizacije (WHO) kao grupa visokog prioriteta i kritične važnosti za zdravlje ljudi kompletno zabrane za upotrebu u veterinarskoj medicini. Na sreću, posle veliko angažovanja Federacije veterinara Evrope, ova rezolucija je odbačena. Više godina unazad ukazuje se sve veća potreba za profilisanjem stručnjaka iz oblasti Veterinarske farmakologiuje i toksikologije koji će svojim znanjem, a vremenom i iskustvom moći da zadovolje zahteve nauke, struke, privrede i državnih institucija koje se bave registracijom, kontrolom proizvodnjom i prometom veterinarskih lekova. Stručno usavršavanje u vidu stručne specijalizacija iz Veterinarske farmakologije i toksikologije, predviđeno usvojenim planom i programom, a koje će se izvoditi na Fakultetu veterinarske medicine, Univerziteta u Beogradu namenjeno je polaznicima sa završenim Fakutetom veterinarske medicine, farmacije i medicine. Propisivanje lekova na recept je po definiciji pisano uputstvo doktora veterinarske medicine ovlašćenom licu u veterinarskoj i humanoj apoteci kako da spravi i izda lek. Takođe, na receptu se objašnjava vlasniku životinje kako da primeni lek (ukoliko za to nije potrebno stručno znanje). Sam postupak propisivanja lekova u veterinarskoj med

Published
2024

8. Pharmacological effects of monoterpene carveol on the neuromuscular system of nematodes and mammals

Author

Stojković, Maja, Todorović, Zoran, Protić, Dragana, Stevanović, Strahinja, Medić, Dragana, Charvet, Claude L., Marjanović, Djordje, Nedeljković Trailović, Jelena, Trailović, Saša M., Stojković, Maja, Todorović, Zoran, Protić, Dragana, Stevanović, Strahinja, Medić, Dragana, Charvet, Claude L., Marjanović, Djordje, Nedeljković Trailović, Jelena, and Trailović, Saša M.

Abstract

The control of parasitic nematode infections relies mostly on anthelmintics. The potential pharmacotherapeutic application of phytochemicals, in order to overcome parasite resistance and enhance the effect of existing drugs, is becoming increasingly important. The antinematodal effects of carveol was tested on the free-living nematode Caenorhabditis elegans and the neuromuscular preparation of the parasitic nematode Ascaris suum. Carveol caused spastic and geraniol atonic paralysis in C. elegans. In A. suum carveol potentiated contractions induced by acetylcholine (ACh) and this effect was confirmed with two-electrode voltage-clamp electrophysiology on the A. suum nicotinic acetylcholine receptor expressed in Xenopus oocytes. However, potentiating effect of carveol on ACh-induced contractions was partially sensitive to atropine, indicates a dominant nicotine effect but also the involvement of some muscarinic structures. The effects of carveol on the neuromuscular system of mammals are also specific. In micromolar concentrations, carveol acts as a non-competitive ACh antagonist on ileum contractions. Unlike atropine, it does not change the EC50 of ACh but reduces the amplitude of contractions. Carveol caused an increase in Electrical Field Stimulation-evoked contractions of the isolated rat diaphragm, but at higher concentrations it caused an inhibition. Also, carveol neutralized the mecamylamine-induced tetanic fade, indicating a possibly different pre-and post-synaptic action at the neuromuscular junction.

Published
2024

9. Perspektive i pravci razvoja novih antihelmintika u veterinarskoj medicini

Author

Trailović, Saša M., Marjanović, Đorđe S., Medić, Dragana, Marić, Tihomir, Trailović, Saša M., Marjanović, Đorđe S., Medić, Dragana, and Marić, Tihomir

Abstract

Rastući nivo rezistencije parazita na antiparazitske lekove, kao i rigorozni standardi za maksimalne nivoe rezidua lekova u jestivim životinjskim tkivima, predstavljaju značajan izazov za savremenu veterinarsku farmakoterapiju. Parazitske nematode uzrokuju značajan morbiditet i smrtnost životinja ali i ljudi širom sveta. Takođe, uzrok su velikih gubitaka u proizvodnji hrane. Kontrola infekcija ovim parazitima oslanja se na efikasnu primenu anthelmintika, ali učestala primena istih anthelmintičkih jedinjenja za masovnu hemoterapiju dovodi do razvoja rezistencije na lekove. Konstantno postoji potreba da se identifikuju nova jedinjenja za razvoj potencijalnih anthelmintika. Sa drige strane, neuromišićni sistem parazitskih nematoda se pokazao kao efikasna farmakološka meta za za ove lekove. Neki od najčešće korišćenih antiparazitskih lekova su agonisti nikotinskih acetilholinskih receptora (nAChRs) (imidazotiazoli i tetrahidropirimidini) ili aktivatori glutamat-zavisnih hloridnih kanala (GluCls) i GABA-receptora (makrociklični laktoni). Holinergički agonisti kao što su levamisol, pirantel i oksantel selektivno otvaraju ligand-zavisne acetilholinske jonske kanale eksprimirane u mišićima zida tela nematoda da izazovu spastičnu kontrakciju mišićnih ćelija što dovodi do paralize crva. Predlažemo u cilju poboljšanja postojeće farmakoterapije i razvoja novih lekova istraživanja u sledećim pravcima: 1. Istraživanje efikasnosti kombinacija postojećih GABAergičnih i holinergičkih lekova za povećanje efikasnosti; 2. Istraživanje potencijalnih novih meta za anthelmintike (muskarinski ACh receptor i serotonergički MOD 1 receptor); 3) Novu namenu postojećih lekova, namenjenim drugim indikacijama koji ispoljavaju potencijalna antihelmintička svojstva; 4) Antinematodna svojstva terpenoidnih aktivnih sastojaka (AI) biljnih esencijalnih ulja i potencijalne kombinacija AI i postojećih lekova.

Published
2024

10. Classification of spent Li-ion batteries based on ICP-OES/X-ray characterization of the cathode materials

Author

Medić Dragana V., Milić Snežana M., Alagić Slađana Č., Đorđević Ivan N., and Dimitrijević Silvana B.

Subjects
libs sorting, instrumental analysis, lithium cobalt oxide, recycling, Chemical technology, TP1-1185
Abstract

Development of lithium-ion batteries (LIBs) during the latest decades resulted in improved performances of the new integrated cathode materials and in their wide applications. This rapid expansion of new materials led to the intensive replacement of the old-fashioned, traditional materials and increased a simultaneous accumulation of both kinds of materials at extremely hazardous electronic waste sites, which additionally increased an urgent need for their recycling. Most importantly, in this way, spent LIBs may further serve as a significant source of valuable metals such as Li and cobalt. However, one of the key problems in LIBs recycling is the absence of a precise battery classification/sorting based on the chemical composition of the used cathode material. In this paper, characterization of the cathode material was performed regarding chemical composition of 40 samples of spent LIBs using inductively coupled plasma - optical emission spectrometry and X-ray diffraction. Preparation of the samples, (pretreatment) included: discharging, dismantling, separation of the main components (cathode, anode and the separator), and detachment of the cathode material from the aluminium foil. The obtained results showed that, in the investigated commercially available LIBs, lithium cobalt oxide was the most frequently used (cathode) material. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. OI172031, Grant no. III46010, and Grant no. TR34024]

Published
2020
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12. Sustainable Processes of Biosorption of Pb(II) Ions from Synthetic Wastewater Using Waste Biomass from Mullein Leaves.

Author

Tasić, Žaklina, Nujkić, Maja, Savić Gajić, Ivana, Medić, Dragana, and Milić, Snežana

Abstract

The aim of this study is to evaluate mullein (Verbascum thapsus) as a cost-effective and sustainable adsorbent for the biosorption of Pb(II) ions from synthetic wastewater samples. Biosorption of mullein was investigated as a function of initial Pb(II) concentration (25–400 mg L−1), biosorbent dosage (2–20 g L−1), solution pH (3–7), and contact time (10–120 min). Mullein as a material with a high affinity for Pb(II) ions had a biosorption efficiency of 98.56% under the optimal conditions: pH 6, initial concentration of Pb(II) at 100 mg L−1, contact time of 90 min, and biosorbent dosage of 20 g L−1. The FTIR spectra of mullein leaves showed that oxygen-containing functional groups on the surface are potentially active sites for the biosorption of Pb(II) ions. EDS analysis and the pHPZC value confirmed the adsorption of Pb(II) ions at the active sites of the mullein. Kinetic and isotherm data enabled insights into the modes of Pb(II) biosorption on the mullein surface which were best explained with the pseudo-second-order kinetic model and the Freundlich adsorption isotherm. Biosorption occurs on the mullein surface via multilayer adsorption. The reusability of mullein showed that the native biosorbents can be reused five times, showing the economic and sustainable benefit of this low-cost biosorbent material. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Cobalt recovery from spent lithium-ion batteries by leaching in H2SO4-N2 and H2SO4-O2 systems followed by electrochemical deposition.

Author

Medić, Dragana V., Tasić, Žaklina Z., Nujkić, Maja M., Dimitrijević, Silvana B., Đorđievski, Stefan S., Alagić, Slađana Č., and Milić, Snežana M.

Subjects
METAL coating, METAL recycling, COPPER, OXIDE coating, SCANNING electron microscopy
Abstract

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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14. The capacities of Hedera helix from the Bor region for PAH accumulation in the root and implications for phytostabilization

Author

Papludis, Aleksandra, Alagić, Slađana, Milić, Snežana, Medić, Dragana, Zlatanović, Ivana, Nikolić, Jelena, and Stankov-Jovanović, Vesna

Subjects
soil pollution, PAHs, General Materials Science, Hedera helix, phytostabilization
Abstract

Polycyclic aromatic hydrocarbons (PAHs) are considered as the pollutants of highest priority, and their remediation is of a global concern. The purpose of this study was to investigate the phytoremediation potential of Hedera helix (Hh) determining the content of 16 priority PAHs in its soil and root samples collected from the rural and industrial zones of the Bor's municipality (Serbia). The content of Ʃ16 PAHs in the soils was: 326.49 mg/kg at the site Borsko jezero to maximal 1937.64 mg/kg at the site Slatinsko naselje. The level of soil pollution (depending on the concentration of S16 PAHs), was high at many tested sites and it was under the significant influence of anthropogenic activities. The concentration for S16 PAHs in the samples of roots ranged from 480.71 mg/kg at the site Krivelj to 1748.32 mg/kg at the site Naselje Sunce. Interestingly, the extremely toxic benzo(a)pyrene, was not detected in the roots of Hh. Bioconcentration factors (BCFs) were applied to determine the capacity of Hh for PAH accumulation in the root, and consequently, for determination of its phytostabilization potential. In most cases, BCF values were higher at the locations from UI zone. The calculated BCFs were higher for LMW PAHs than for HMW PAHs. At the majority of the investigated locations, the tested plant species was especially successful in the root accumulation of the compounds such as acenaphthene, fluorene, anthracene, dibenzo(a,h)anthracene, and the sum of benzo(k)fluoranthene and benzo(b)fluoranthene. These findings showed that Hh can be successfully used in phytostabilization of many PAHs.

Published
2023
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16. Propisivanje lekova na recept

Author

Trailović, Saša, Milovanoviić, Mirjana, Ivanović, Saša, Marjanović, Đorđe, Medić, Dragana, Trailović, Saša, Milovanoviić, Mirjana, Ivanović, Saša, Marjanović, Đorđe, and Medić, Dragana

Abstract

Propisivanje lekova na recept je po definiciji pisano uputstvo doktora veterinarske medicine ovlašćenom licu u veterinarskoj i humanoj apoteci kako da spravi i izda lek. Takođe, na receptu se objašnjava vlasniku životinje kako da primeni lek (ukoliko za to nije potrebno stručno znanje). Sam postupak propisivanja lekova u veterinarskoj medicini je privilegija i obaveza isključivo doktora veterinarske medicine. Pisanje veterinarskog recepta objedinjuje celokupno znanje iz veterinarske farmakologije, toksikologije i kliničke prakse. Istovremeno, pisanje recepata predstavlja i veštinu da se celokupno znanje doktora veterinarske medicine iskoristi za dobrobit naših pacijenata. Novi propisi i pravila u propisivanju lekova na recept zahtevaju obnovu znanja i podsećanje na osnovna pravila propisivanja. Radionica: PROPISIVANJE LEKOVA NA RECEPT, obuhvatiće: 1. Pravilnike o propisivanju leka na recept (veterinarski i humani), elektronski recepti u humanoj praksi, najavu elektronskih recepata u veterinarskoj medicini u EU, pravilo kaskada i ulazni test; 2. Propisivanje veterinarskih lekova na recept, osnovna pravila i primere; 3. Propisivanje humanih lekova na veterinarski recept sa posebnim osvrtom na propisivanje psihotropnih kontrolisanih supstanci; 4. Primere propisivanja lekova, veterinarskih i humanih, vežbanje propisivanja lekova, Izlazni test.

Published
2023

17. Dezinfekciono delovanje uv lampi

Author

Zdravković, Nemanja, Radanović, Oliver, Zdravković, Zorica, Grujović, Teodora, Marjanović, Đorđe, Medić, Dragana, Cvetković, Ružica, Ninković, Milan, Zdravković, Nemanja, Radanović, Oliver, Zdravković, Zorica, Grujović, Teodora, Marjanović, Đorđe, Medić, Dragana, Cvetković, Ružica, and Ninković, Milan

Abstract

Priča o prevenciji i kontroli zaraznih bolesti ostaje otvorena jer se niz patogenih bakterija iznova pojavljuje kao izazivač infekcija. Da bi se taj problem prevazišao, antibiotici su bili dominantni tokom prethodne ere. Rezistencija kao fenomen kojim se patogeni mikroorganizmi opiru dejstvu lekove je postavo izuzetno raširen u svetu. Više naučnih pravaca se razvija u svrhu prevazilaženja ovog problema, pa je tako fotodinamička inaktivacija definisana u platformu za otkrivanje i razvoj antimikrobnih sredstava. Koncept fotodinamičke inaktivacije je prilično jednostavan i zahteva izlaganje mikroba energijom svetla koja uzrokuje pobuđivanje molekula, što rezultira proizvodnjom singlet kiseonika ili drugim reaktivnim kiseoničkim vrstama koje reaguju sa intracelularnim komponentama, a posledično dovode do ćelijske inaktivacije. To je oblast sve većeg interesovanja, kao i istraživanja u smerovima: (1) da se identifikuju fotohemijski i fotofizički mehanizmi uključeni u inaktivaciju, (2) da razviju moćni i klinički kompatibilni fotosenzibilizatori, (3) da se razume kako na fotoinaktivaciju utiču ključni mikrobni fenotip elementi (rezistencija na više lekova i efluks, virulencija i determinante patogeneze, biofilmovi), (4) da se istraže nove platforme za isporuku inspirisane trenutnim trendovima u farmakologiji i nanotehnologijama i (5) za identifikaciju fotoinaktivacije primene izvan kliničkog okruženja kao što je životna sredina tj. dezinfekciona sredstva., The prevention and control of infectious diseases problem remains open as a number of pathogenic bacteria re-emerge as the cause of infection. To overcome this problem, antibiotics were dominant during the previous era. Resistance as a phenomenon by which pathogenic microorganisms overcome the effect of drugs has become extremely widespread in the world. A lot of scientific attempts in different directions are being developed in order to overcome this problem, so photodynamic inactivation has been defined as a platform for the discovery and development of antimicrobial agents. The concept of photodynamic inactivation is quite simple and requires exposure of microbes to light energy that causes molecular excitation, resulting in the production of singlet oxygen or other reactive oxygen species that react with intracellular components, and consequently lead to cellular inactivation. It is an area of increasing interest, as well as research in the directions: (1) to identify the photochemical and photophysical mechanisms involved in inactivation, (2) to develop potent and clinically compatible photosensitizers, (3) to understand how photoinactivation is affected by key microbial phenotype elements (multidrug resistance and efflux, virulence and pathogenesis determinants, biofilms), (4) to explore new delivery platforms inspired by current trends in pharmacology and nanotechnologies and (5) to identify photoinactivation applications outside the clinical setting such as life the middle ie disinfectants.

Published
2023

18. Kultivisanje, održavanje i primena Caenorhabditis elegans u biomedicinskim istraživanjima

Author

Medić, Dragana, Marjanović, Đorđe, Medić, Dragana, and Marjanović, Đorđe

Abstract

Caenorhabditis elegans je neparazitska nematoda koja živi u zemljištu. Prvi podaci o primeni C. elegans u eksperimentalne svrhe potiču još iz 1965. kada je Sidni Brener, južnoafrički biolog, proučavao ponašanje i razvoj životinja (naročito neuralni razvoj) na ovoj nematodi. Nedugo zatim C. elegans je postao jedan od napopularnijih eksperimentalnih modela u biomedoicinskim istraživanjima. Tome u prilog govori činjenica da su do danas tri Nobelove nagrade dodeljene naučnicima koji su istraživanja upravo radili na C. elegans, a pored toga, dobijena su i mnoga druga značajna otkrića u različitim oblastima biomedicine. Veoma brz i kratak životni ciklus (3-5 dana), velikog broja potomaka i lako kultivisanja u laboratorijskim uslovima neke su od glavnih prednosti C. elegans. Za kultivaciju ove nematode koristi se podloga za rast nematoda (Nematode Growth Median) u koju se dodaje E. coli OP 50 kojom se C. elegans hrani. Postoje dva pola: samooplodni hermafroditi i mužjaci. U najvećem broju odrasli C. elegans su 1 mm dugi hermafroditi sa reproduktivnim ciklusom od 2,5-4 dana na sobnoj temperaturi i srednjim životnim vekom od približno 18-20 dana na 20°C. Nakon izleganja, C. elegans može ili da se razvije direktno kroz četiri stadijuma larve (L1-L4) ili da nastavi sa stadijumom „dauer“ larve, umesto stadijuma L3. Faza „dauer“ larve je razvojno zaustavljena faza disperzije koja se koristi za preživljavanje u nepovoljnim uslovima. Kada se nepovoljni uslovi povuku, C. elegans se može oporaviti i razviti u stadijum larve L4. C. elegans se intenzivno koristi u ispitivanju apoptoze, transdukcije, starenja, zelenog fluorescentnog proteina i njegove uloge u ekspresiji gena, ispitivanju jonskih kanala, testiranju modela bolesti, ispitivanju lekova i dr. U našoj laboratoriji C. elegans koristimo u ispitivanjima mehanizma dejstva antinematodnih lekova i mehanizmima razvoja rezistencije nematoda.

Published
2023

20. Actual contamination of the Danube and Sava rivers at Belgrade (2013)

Author

Antonijević Milan D., Arsović Marija, Čáslavský Josef, Cvetković Vesna, Dabić Predrag, Franko Mladen, Ilić Gordana, Ivanović Milena, Ivanović Nevena, Kosovac Milica, Medić Dragana, Najdanović Slobodan, Nikolić Milica, Novaković Jovana, Radovanović Tatjana, Ranić Đurđina, Šajatović Bojan, Špijunović Gorica, Stankov Ivana, Tošović Jelena, Trebše Polonca, Vasiljević Olivera, and Schwarzbauer Jan

Subjects
river systems, state of pollution, organic pollutants, heavy metals, screening analyses, non-target screening, Chemistry, QD1-999
Abstract

This study is focussed on a comprehensive investigation on the state of pollution of Danube and Sava rivers in Belgrade region. Different complementary analytical approaches have been used covering both (i) organic ccontaminants in river water by target analyses of hormones and neonicotinoids as well as non-target screening analyses and (ii) heavy metals in sediments. Finally, some common water quality parameters have been analysed. The overall state of pollution is on a moderate level. Bulk parameters did not reveal any unusual observation. Also quantification of preselected organic contaminants did not point to elevated pollution. A more significant contamination was measured for chromium, nickel, zinc and partially copper in sediments with values above target values according to Serbian regulations. Lastly, non-target screening analysis revealed a wider spectrum of organic contaminants comprising pharmaceuticals, technical additives, personal care products and pesticides. The study presented a comprehensive view on the state of pollution of Sava and Danube rivers and is the base for setting up further monitoring programs. As a superior outcome it has been illustrated how different chemical analyses can point to different assessments of the river quality. The comparison of target and non-target analyses pointed to potential misinterpretation of the real state of pollution.

Published
2014
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21. Cobalt extraction from spent lithium-ion battery cathode material using a sulfuric acid solution containing SO2.

Author

Medić, Dragana V., Sokić, Miroslav D., Nujkić, Maja M., Đorđievski, Stefan S., Milić, Snežana M., Alagić, Slađana Č., and Antonijević, Milan M.

Abstract

To increase the degree of cobalt (Co) extraction, the process of the cathode material leaching was performed in a sulfuric acid (H2SO4) solution containing sulfur dioxide (SO2) as a reducing agent. To provide a high resolution of the obtained results, frequent monitoring of Co concentrations in leached solution was conducted using an ultraviolet–visible spectrophotometer with several specific modifications related to the connection of the reaction vessel with the instrumental cuvette. The maximum degree of Co leaching (99.4%) was achieved with H2SO4 concentration of 3 mol/L, solid phase concentration of 33 g/L, temperature of 85 °C, SO2 volume flow of 2 L/min, and leaching time of 60 min. The results of the performed kinetic analyses indicated that the Avrami equation best describes the investigated leaching process, which later was supported by the results of X-ray diffraction and scanning electron microscopy–energy-dispersive X-ray spectroscopy analyses. Also, the activation energy of 28 ± 3 kJ/mol is in favor of the fact that the process of Co leaching was controlled by the factors, such as diffusion and chemical reaction. The results of this study indicated that SO2 can be used as an effective reducing agent in the investigated process. [ABSTRACT FROM AUTHOR]

Published
2023
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22. Valorizacija kobalta iz katodnog materijala istrošenih litijum-jonskih baterija

Author

Medić, Dragana, Milić, Snežana, Antonijević, Milan, and Sokić, Miroslav

Subjects
lithium-ion batteries, cathode material, leaching, valorization, reducing agent, kinetic models, electrolysis, litijum-jonske baterije, katodni materijal, luženje, valorizacija, redukciono sredstvo, kinetički modeli, elektroliza
Abstract

U doktorskoj disertaciji ispitivana je mogućnost valorizacije kobalta iz istrošenih litijumjonskih baterija. Detaljno je proučen i razvijen svaki stadijum u procesu reciklaže baterija. Primenom TGA analize određena je vrednost optimalne temperature za odvajanje katodnog materijala od aluminijumske folije. Metode ICP-OES i XRD korišćene su za razvoj metodologije za klasifikaciju litijum-jonskih baterija na osnovu hemijskog sastava katodnog materijala. Razvijena je i aparatura za praćenje koncentracije kobalta u lužnim rastvorima, uz dobijanje preciznih informacija o valentnom stanju jona kobalta. Utvrđeni su optimalni uslovi luženja katodnog materijala u atmosferi azota, kiseonika i sumpor-dioksida. Sprovedena kinetička analiza procesa luženja katodnog materijala u tri ispitivana sistema za luženje, ukazala je da se rastvaranje katodnog materijala u atmosferi N2, O2 i u prisustvu redukcionog sredstva, odvija u jednom stadijumu. U reakciji rastvaranja katodnog materijala u atmosferi N2 i O2 nastaje mešoviti oksid Co3O4. Nagrađeni oksid kobalta formira teško rastvorni, porozni sloj, koji sa vremenom raste. Narastajući sloj Co3O4 sprečava transport jona Li i Co iz katodnog materijala, kao i transport agensa za luženje do reakcione površine. Posledice navedenog su manje vrednosti stepena izluženja kobalta. Za razliku od sistema luženja katodnog materijala u atmosferi O2 i N2, mehanizam izluženja Co u atmosferi SO2 odvija se u jednom stadijumu, bez formiranja čvrstog Co3O4 kao produkta reakcije luženja. Snimljeni ciklični voltagrami ukazali su da dobijeni lužni rastvori nisu pogodni za elektrolitičko taloženje kobalta, i da je za veći stepen efikasnosti procesa neophodno povećati pH i električnu provodljivost rastvora. In this doctoral dissertation, the possibility of valorization of cobalt from spent lithium-ion batteries was investigated. Each stage in the battery recycling process was studied and developed in detail. Using TGA analysis, the optimal temperature value for separation of the cathode material from the aluminium foil was determined. The ICP-OES and XRD methods were used to develop the methodology for classification of lithium-ion batteries based on the chemical composition of the cathode material. In addition, the apparatus for monitoring cobalt concentration in the leach solutions was developed, providing precise information on the valence state of cobalt ions. Optimal conditions for the cathode material leaching process in the atmospheres of nitrogen, oxygen and sulfur-dioxide were determined. The performed kinetic analysis of cathode material leaching in the three investigated leaching systems indicates that dissolution of the cathode material in the N2 and O2 atmospheres and in the presence of a reducing agent, proceeds in one stage. The dissolution reaction of the cathode material in N2 and O2 atmospheres results in the formation of Co3O4 mixed oxide. This oxide forms a hardly soluble porous layer which grows with time. The growing Co3O4 layer prevents the transport of Li and Co ions from the cathode material, as well as the transport of the leaching agents to the reaction surface. Consequently, the values of the degree of cobalt leaching are lower. Unlike the cathode material leaching in O2 and N2 atmosphere, the leaching mechanism of Co in SO2 atmosphere occurs in one stage, without the formation of solid Co3O4 as the product of the leaching reaction. The recorded cyclic voltagrams indicate that the obtained leach solutions are not convenient for electrolytic deposition of cobalt and that in order to achieve higher process efficiency it is necessary to increase the pH value and electrical conductivity of the solution.

Published
2021

27. Corrigendum: Pharmacological effects of monoterpene carveol on the neuromuscular system of nematodes and mammals.

Author

Stojković M, Todorović Z, Protic D, Stevanovic S, Medić D, L Charvet C, Courtot E, Marjanović DS, Nedeljković Trailović J, and Trailović SM

Abstract

[This corrects the article DOI: 10.3389/fphar.2024.1326779.]., (Copyright © 2024 Stojković, Todorović, Protic, Stevanovic, Medić, L. Charvet, Courtot, Marjanović, Nedeljković Trailović and Trailović.)

Published
2024
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